I just bought a 65 reverb head and have replaced the tubes with GE EL34's. I took it to the local repair shop and the tech told me this is a self biasing amp. Is this true? It doesn't have a 12Ax7 tube so I'm assuming it is a later model. Thanks.
It's not truly self biasing but for most purposes, it is. The driver board determines the cathode current and is adjustable. See the adj procedures listed earlier in this heading. Mike.
Tue, 03/25/2014 - 10:01#1
65 Reverb Biasing
I have a 65 Reverb (1976) Head. I purchased the TAD Bias Master. Can anyone tell me the readings (mAs) I should set the bias to for this amp? Range? Thank you.
I set them around 22mA for
1976 says it should have a 12ax7 PI tube. I set them around 22mA for EACH TUBE. That will get you past the crossover distortion threshold and get you good service life. Even 21 won't hurt. Cooler is better unless you get TOO cold and they get nasty sounding. JMHO of course. Mike